It is disappointing that some unions insist on pushing for futile strike action which benefits no one and ­damages the services they deliver to the public

Spokeswoman for Mr Maude

The rebels will bombard Cabinet Office minister Francis Maude with mass phone calls and emails in protest at Government cuts.

The breakaway group, calling itself the Civil Service Rank and File Network, is also calling for walk-outs in a day of action on November 14.

The group has published the telephone, email and fax details of Mr Maude’s Westminster office and ­constituency headquarters in Horsham, Sussex, on its Facebook site.

Last night, a spokeswoman for Mr Maude at the Cabinet Office said: “It is disappointing that some unions insist on pushing for futile strike action which benefits no one and ­damages the services they deliver to the public.

“Pay restraint has helped to protect jobs in the public ­sector and support high-quality ­public services.”

The Cabinet Office declined to comment on the communications blockade.

Mr Maude is being targeted because he is spearheading the Government’s policy to reduce civil service spending and jobs as part of its plans to slash the £11billion public sector budget deficit.

The renegade group is also urging 15-minute “lightning walk-outs” and protest rallies at job centres, town halls and government offices.

On its website, CSRF says: “If we do not beat these attacks, it will embolden employers to drive down the working conditions of all ­workers. The time to stand our ground and fight is now.”

It is understood several Whitehall branches of the ­Public Commercial Service Union – including the Home Office, HM Revenue and Customs and Defra groups – have already voted to take part in a 15-minute stoppage on the day.

The PCS National Executive Committee, which represents about 270,000 public sector staff, is to hold an ­emergency meeting on Wednesday to ­discuss further action.

The rebel CSRF campaign was only launched a fortnight ago after around 250 Revenue and Customs staff in Coventry staged a 15-minute walkout to coincide with a visit by Mr Maude.